package com.atguigu.utils;

import com.alibaba.druid.pool.DruidDataSource;
import com.alibaba.druid.pool.DruidDataSourceFactory;

import java.io.InputStream;
import java.sql.Connection;
import java.sql.SQLException;
import java.util.Properties;

/**
 * @ClassName JdbcUtils
 * @Description TODO
 * @Author lmy
 * @Date 2022/3/30 15:06
 **/
public class JdbcUtils {
    private static DruidDataSource dataSource;
    static { try {
        Properties properties = new Properties();
        // 读取 jdbc.properties 属性配置文件
        InputStream inputStream = JdbcUtils.class.getClassLoader().getResourceAsStream("jdbc.properties"); // 从流中加载数据
        properties.load(inputStream);
// 创建 数据库连接 池
        dataSource = (DruidDataSource) DruidDataSourceFactory.createDataSource(properties); } catch (Exception e) {
        e.printStackTrace();
    }
    }

    /**
     * 获取数据库连接池中的连接
     * @return 如果返回 null,说明获取连接失败<br/>有值就是获取连接成功 */
    public static Connection getConnection(){
        Connection conn = null;
        try {
            conn = dataSource.getConnection();
        } catch (Exception e) { e.printStackTrace();
        }
        return conn; }
    /**
     * 关闭连接，放回数据库连接池 * @param conn
     */
    public static void close(Connection conn){ if (conn != null) {
        try { conn.close();
        } catch (SQLException e) { e.printStackTrace();
        } }
    }
}